Question Pad 5 keep turn on alone when attached to the keyboard cover

[Nesylm]

Excuse me, anyone facing same issue with me? When my xiaomi pad 5 connected to the keyboard cover, it keep turn on the screen when i try to lock it

When pad 5 not connected to the keyboard it not happen. I try factory reset but it still happen.

Here the sample video:

 

[Nesylm]

Many people maybe think it's because notification, but actually that is "don't distrub" mode sign.

So here another more detail video: